Coronavirus : Japan’s mysteriously low virus death rate - BBC News
▻https://www.bbc.com/news/world-asia-53188847
Literally translated, mindo means “people’s level”, although some have translated it as meaning “cultural level”.
It is a concept dating back to Japan’s imperial era and denotes a sense of racial superiority and cultural chauvinism. Mr Aso has been roundly condemned for using it.
But there is no doubt that many Japanese, and some scientists, think there is something about Japan that is different - a so called “Factor X” that is protecting the population from Covid-19.
It is possibly relevant that some aspects of Japanese mores - few hugs and kisses on greeting - have in-built social distancing, but nobody thinks that is the answer.
Does Japan have special immunity?
Tokyo University professor Tatsuhiko Kodama - who studies how Japanese patients react to the virus - believes Japan may have had Covid before. Not Covid-19, but something similar that could have left behind “historical immunity”.
This is how he explains it: When a virus enters the human body, the immune system produces antibodies that attack the invading pathogen.
There are two types of antibody - IGM and IGG. How they respond can show whether someone has been exposed to the virus before, or something similar.
“In a primary (novel) viral infection the IGM response usually comes first,” he tells me. “Then the IGG response appears later. But in secondary cases (previous exposure) the lymphocyte already has memory, and so only the IGG response increases rapidly.”
So, what happened with his patients?
“When we looked at the tests we were astonished... in all patients the IGG response came quickly, and the IGM response was later and weak. It looked like they had been previously exposed to a very similar virus.”
He thinks it is possible a Sars-like virus has circulated in the region before, which may account for the low death rate, not just in Japan, but in much of China, South Korea, Taiwan, Hong Kong and South East Asia.
La résistance des sociétés asiatiques face au #Covid-19 n’aurait rien à voir avec les tests (Taiwan), la discipline et la distanciation sociale (Japon) mais avec l’immunité acquise lors d’autres épidémies. Confiance en la BBC, je poste...